// SPDX-License-Identifier: LGPL-3.0-or-later
#include <gtest/gtest.h>

#include <iostream>

#include "env_mat.h"
#include "fmt_nlist.h"
#include "neighbor_list.h"
#include "soft_min_switch.h"
#include "soft_min_switch_force.h"

class TestSoftMinSwitchForce : public ::testing::Test {
 protected:
  std::vector<double> posi = {12.83, 2.56, 2.18, 12.09, 2.87, 2.74,
                              00.25, 3.32, 1.68, 3.36,  3.00, 1.81,
                              3.51,  2.51, 2.60, 4.27,  3.22, 1.56};
  std::vector<int> atype = {0, 1, 1, 0, 1, 1};
  std::vector<double> posi_cpy;
  std::vector<int> atype_cpy;
  int ntypes = 2;
  int nloc, nall, nnei, ndescrpt;
  double rc = 6;
  double rc_smth = 0.8;
  double alpha = .5;
  double rmin = 0.8;
  double rmax = 1.5;
  SimulationRegion<double> region;
  std::vector<int> mapping, ncell, ngcell;
  std::vector<int> sec_a = {0, 5, 10};
  std::vector<int> sec_r = {0, 0, 0};
  std::vector<int> nat_stt, ext_stt, ext_end;
  std::vector<std::vector<int>> nlist_a_cpy, nlist_r_cpy;
  std::vector<double> sw_value, sw_deriv, du;
  std::vector<double> rij;
  std::vector<int> nlist;
  std::vector<int> fmt_nlist_a;
  std::vector<double> expected_force = {
      2.24044,  -1.75363, -1.50088, -2.54065, 1.08035,  1.93630,  1.12909,
      1.64972,  -1.10112, -2.07854, 0.69062,  -1.29217, 0.14032,  -1.16008,
      1.86286,  1.71311,  0.49339,  -0.59049, -0.88441, -1.66176, 1.09480,
      -0.01957, -0.01188, 0.02612,  0.00000,  0.00000,  0.00000,  0.00000,
      0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,
      0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,
      0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,
      0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,
      0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,
      0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,
      0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,
      0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,
      0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,
      0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.36743,  0.67600,
      -0.43959, -0.03250, -0.00298, 0.00469,  -0.02791, 0.00109,  -0.00167,
      -0.00681, -0.00083, 0.00115,  0.00000,  0.00000,  0.00000,  0.00000,
      0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,
      0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,
      0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,
      0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,  0.00000,
      0.00000,  0.00000,  0.00000,  0.00000,
  };

  void SetUp() override {
    double box[] = {13., 0., 0., 0., 13., 0., 0., 0., 13.};
    region.reinitBox(box);
    copy_coord(posi_cpy, atype_cpy, mapping, ncell, ngcell, posi, atype, rc,
               region);
    nloc = posi.size() / 3;
    nall = posi_cpy.size() / 3;
    nnei = sec_a.back();
    ndescrpt = nnei * 4;
    nat_stt.resize(3);
    ext_stt.resize(3);
    ext_end.resize(3);
    for (int dd = 0; dd < 3; ++dd) {
      ext_stt[dd] = -ngcell[dd];
      ext_end[dd] = ncell[dd] + ngcell[dd];
    }
    build_nlist(nlist_a_cpy, nlist_r_cpy, posi_cpy, nloc, rc, rc, nat_stt,
                ncell, ext_stt, ext_end, region, ncell);
    nlist.resize(static_cast<size_t>(nloc) * nnei);
    rij.resize(static_cast<size_t>(nloc) * nnei * 3);
    for (int ii = 0; ii < nloc; ++ii) {
      // format nlist and record
      format_nlist_i_cpu<double>(fmt_nlist_a, posi_cpy, atype_cpy, ii,
                                 nlist_a_cpy[ii], rc, sec_a);
      for (int jj = 0; jj < nnei; ++jj) {
        nlist[ii * nnei + jj] = fmt_nlist_a[jj];
      }
      std::vector<double> t_env, t_env_deriv, t_rij;
      // compute env_mat and its deriv, record
      deepmd::env_mat_a_cpu<double>(t_env, t_env_deriv, t_rij, posi_cpy,
                                    atype_cpy, ii, fmt_nlist_a, sec_a, rc_smth,
                                    rc);
      for (int jj = 0; jj < nnei * 3; ++jj) {
        rij[ii * nnei * 3 + jj] = t_rij[jj];
      }
    }
    sw_value.resize(nloc);
    sw_deriv.resize(static_cast<size_t>(nloc) * nnei * 3);
    deepmd::soft_min_switch_cpu<double>(&sw_value[0], &sw_deriv[0], &rij[0],
                                        &nlist[0], nloc, nnei, alpha, rmin,
                                        rmax);
    du.resize(nloc);
    for (int ii = 0; ii < nloc; ++ii) {
      du[ii] = 1.0 - ii * 0.1;
    }
  }
  void TearDown() override {}
};

TEST_F(TestSoftMinSwitchForce, cpu) {
  std::vector<double> force(nall * 3);
  deepmd::soft_min_switch_force_cpu(&force[0], &du[0], &sw_deriv[0], &nlist[0],
                                    nloc, nall, nnei);
  EXPECT_EQ(force.size(), expected_force.size());
  for (int jj = 0; jj < force.size(); ++jj) {
    EXPECT_LT(fabs(force[jj] - expected_force[jj]), 1e-5);
  }
  // for (int ii = 0; ii < nall * 3; ++ii){
  //   printf("%8.5f, ", force[ii]);
  // }
  // printf("\n");
}
